1. Field of the Invention
The present invention relates generally to semiconductor die bonding machines and more particularly to a bonding machine which will align and electrically connect a micro leadframe to a semiconductor die and main leadframe in a single operation.
2. Description of the Prior Art
A semiconductor die may be electrically connected to a main leadframe by utilizing a micro leadframe having a plurality of leads, each of which is bonded on its inner end to a contact pad of the semiconductor die and bonded on its outer end to an individual lead of the main leadframe. The problem encountered in bonding machines utilizing leadframes has been the difficulty involved in the alignment of the micro leadframe leads with the contact pads of the semiconductor die and the leads of the main leadframe. Bonding machines such as that described in patent application Ser. No. 202,258, referenced hereinabove, utilize complicated optical systems to achieve alignment of each individual micro leadframe with the semiconductor die contact pads and the main leadframe leads. The instant invention, through its use of alignment holes, achieves the mechanized alignment of the micro leadframes.
Another problem associated with micro leadframe bonding has been the lack of a strong platform to which the semiconductor die may be affixed for grounding and heat sinking and which adds strength to the die connections. Prior bonding machines, such as that described in patent application Ser. No. 202,258, referenced hereinabove, could not affix the semiconductor die to the main leadframe platform because the platform interfered with alignment and electrical connection. The instant invention is able to utilize the main leadframe platform, thereby providing a grounded heat sink for the semiconductor die and achieving a more rugged bonded configuration.
There is therefore an unfilled need in the industry for a bonding machine in which the alignment of the semiconductor die contact pads, the leads of the micro leadframe and the main leadframe leads can be easily and mechanically accomplished. The instant invention performs such a bonding operation utilizing a specially designed micro leadframe; such a micro leadframe and a process and machine for the manufacture thereof is described in the patent application entitled "Improved Aluminum Micro Leadframe and a Process and a Machine for the Manufacture Thereof," filed on the same date as the instant application and referenced hereinabove.